Feeder tap rule?

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ecuinc

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I have a customer who wants to add another extraction well. he currently has six well control panels that need a 20amp single phase 240 to each panel. These panels are being feed from a 50amp two ploe breaker. from this breaker it goes 500 feet underground in a conduit with #4's to a pull box. From this pull box he has spliced on #8's to each of the 6 wells (approx. 100feet).

So my question is, is this tap a code violation?
 
don_resqcapt19

don_resqcapt19

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Location
Illinois
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retired electrician
240.21(B)(5) would permit the use of tap conductors in this application. <BR><BR> I agree with the previous poster, that there are no tap conductors in the application described in the original post.
 
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ecuinc

Member
Maybe i didnt explain it right. Let me try again. At the load center, there is a 50amp 2 pole 240 Volt breaker. The #4 THHN wire goes in a 1 1/4" conduit under ground aprrox 500' to a traffic rated pull box in the ground. At this pull box, they have spliced on 4 sets of #8 THHN wire to feed four 20amp well control panels. The well panels are located approx 100' away from the pull box where the splices have been made. And i just found out that 200 feet back up the road they splice on two other wells on the same feeder.

Instant that considered a tap?
 
Smart $

Smart $

Esteemed Member
Location
Ohio
ecuinc said:
...

Instant that considered a tap?
Click to expand...
Many call it a tap, simply because of the smaller wire spliced into the larger wire... but a tap is where the feeder's COPD rating is greater than the tap conductor's ampacity. 8AWG CU @ 75? has an allowable ampacity of 50A. With derating you could go as low as 46A.... and it will still be protected by the 50A OCPD... so no, it does not qualify as a tap.
 
Smart $

Smart $

Esteemed Member
Location
Ohio
PS: If there are pump motors supplied by the well control panels, it is even possible that the derated ampacity can be lower than 46A and still be protected by the 50A feeder OCPD
 
augie47

augie47

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Tennessee
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State Electrical Inspector (Retired)
Most of us see potential problems, but in direct answer to your question, read 240.2:

Tap Conductors. As used in this article, a tap conductor is
defined as a conductor, other than a service conductor, that
has overcurrent protection ahead of its point of supply that
exceeds the value permitted for similar conductors that are
protected as described elsewhere in 240.4.

A 50 amp breaker would normally be an acceptable OCPD for your #8 wire, so the #8s are not considered "taps" by the Code.
You have a 50 amp circuit with one portion having an over sized conductor.

( and the potential fora bunch of problems..:D )
 
kwired

kwired

Electron manager
Location
NE Nebraska
Even if the 4 AWG portion of the circuit had higher overcurrent protection, this would be a compliant install as long as the 4 AWG was protected at or below its ampacity, and then the taps would start where the 8 AWG is connected. Since this is an outdoor installation (from what I understand) there is no limit to the tap length, but in that case the taps would need to end in an overcurrent device rated no more than the ampacity of the tap conductor - which would be 50 amps max.
 
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